While Cloud Atlas spans centuries, The Bone Clocks takes place over the relatively short space of six decades. "Its main arc is not that of history but of a life," he says. "That grounds it in people, in human mud, more than Cloud Atlas as it's much more concerned with relationships, psychology and the personae we are as we move through life."
Ostensibly, it's the story of Holly Sykes, who we first meet as a rebellious teenager growing up in Kent in 1984. Becoming more of a background presence as the novel progresses, she returns to the foreground in the final section, which occurs in a grim, post-apocalyptic future.
"Holly is sometimes the point of view character and sometimes she's not," says Mitchell. "I wanted the scope to do a portrait of someone being a sister, a daughter, a mother, a partner, a widow, a grandmother and a guardian. I was especially interested in that middle era of life - whatever you are when you're in your 50s - that's Bone Clocks territory in a way that it wasn't for Cloud Atlas."
Beginning with Holly obsessing over Talking Head's classic 1979 album Fear of Music, Mitchell has drawn heavily on his past for the various details of her life. "I give myself a lot of headaches when I write the books when it comes to making them work," says the 45-year-old who, like Holly, was born in 1969. "But when I can make it easy on myself, I do so. By having a character your own age, it cuts down on the arithmetic because you will know how old she is in a certain year because you were that age as well. We're both synced-up with the world in the same place, at the same points, so we'll be the same age when this or that happened in popular British culture."
Although some critics have compared him to Martin Amis, Mitchell claims there is also much of himself in cynical author Crispin Hershey, who narrates the fifth section. "He's me just run amok," he laughs. "I bite my tongue, keep my mouth shut and take the judicious course but Crispin actually says things and does things I don't dare to, including taking the ultimate critic's revenge."
But like sociopathic Cambridge student Hugo Lamb and war correspondent Ed Brubeck, Crispin is shown the right path by his encounters with Holly. "He has the potential for redemption and that's what she does for the others as well. She doesn't even know she's doing it but she's offering them a way to become the better men they really are on the inside. They either take that offer, or reject it, or end up somewhere in between."
Unfortunately, the same cannot be said for shady Kiwi operative Elijah D'Arnoq, who inducts Hugo Lamb into the clandestine ranks of his sinister organisation. "He's the grandson of Mr D'Arnoq from Cloud Atlas, so he isn't the same character but he does have the same distinctive name, which is almost 'Conrad' backwards," says Mitchell, referring to Cloud Atlas' opening story strand, which harked back to the Chatham Islands during the 19th century. "But everyone has to come from somewhere and it pleases me that, for all I know, I'm one of the few literary connections that the Chathams has with the outside world. I've got a few good memories of the place, so that makes me happy as it's one of those places that's on the edge of things."
The Bone Clocks also boasts links to 2006's Black Swan Green and even 2010's The Thousand Autumns Of Jacob De Zoet which, on the surface at least, appeared to be a straightforward depiction of 18th colonial Japan. "It was a historical novel and I wanted it to be one, although retrospectively there are some things that will now make a lot more sense," says Mitchell. "But what I try and do is always make it optional as I don't want the books to be like a prequel or a sequel in any way. Each one has to be an independent reading experience otherwise people have to buy the whole backlist and spend a month reading it all, which isn't fair.
"It has to work on its own terms but if you do know who these characters are then you will get that extra layer, those extra rooms and compartments of a character that otherwise you wouldn't be able to access."
The Bone Clocks (Sceptre $37.99) is out now.